Timely and effective disinfection is a critical tool in controlling the spread of deadly viruses, such as the recent outbreak of Ebola in Africa. Ebola virus is highly transmittable and can remain viable on solid surfaces for several days. Bodily fluids generated by infected individuals are extremely infectious and pose great risk to both healthcare workers and the general public. Therefore, it is of critical importance to comprehensively disinfect all surfaces exposed to Ebola virus, such as personal protective equipment (PPE), transport vehicles, and surfaces in the patient care environment.
Currently, WHO protocols call for a 1:10 diluted 5.25% bleach mist to be sprayed on surfaces to kill Ebola virus, and for the bleach mist to be left on for at least 10 minutes. (Public Health Agency of Canada. (2014, Aug. 22). Retrieved from: http://www.phac-aspc.gc.ca/lab-bio/res/psds-ftss/ebola-eng.php). Especially for viruses that are transmitted through bodily fluids, it is critical that all contaminated surfaces are thoroughly covered. However, it is difficult to guarantee sufficient topical coverage because bleach is transparent. In addition, surfaces such as typical PPE suits are hydrophobic and bleach mist forms droplets upon contact, which do not fully cover the surface. Bleach droplets roll off of surfaces and therefore do not maintain the requisite 10 minutes of contact time necessary to inactive virus, leaving surfaces potentially contaminated. The WHO protocol did not prevent healthcare workers from being infected with Ebola during the recent outbreak as more than 850 healthcare personnel are known to have become infected, of whom over 500 had died.
Indeed, despite having access to protective equipment and following disinfection protocols, a CDC report suggests that healthcare workers are the group most affected by emerging infectious diseases. (Centers for Disease Control and Prevention. (2005, July). http://wwwnc.cdc.gov/eid/article/11/7/04-1038_article) For instance, during the SARS outbreak, healthcare workers comprised 21% of all cases. Similar to Ebola, the likely cause of viral transmission is the inherent difficulty of covering all infected surfaces with bleach mist and having it stay on infected areas for 10 minutes to kill the virus.
Thus, there is an urgent need for a more effective approach of disinfection that is readily usable with conventional disinfectants (e.g., bleach), allows for easy visualization without leaving stains, exhibits good stickiness to surfaces, is easily stored and transported, is safe and environmentally friendly, and is suitable for use in hospital and field settings.